Adriamycin is one of the most widely used and useful anti-tumor drugs available. However, because of its cardiac toxicity, its use is limited. Various investigators have sought analogs of adriamycin which retain the antitumor activity of the parent antibiotic but which lack the undesirable cardiac toxicity. See for example, U.S. Pat. No. 4,046,878 which discloses daunorubicin derivatives, including 4-demethoxydaunorubicin and British Pat. No. 1,003,383 which discloses daunorubicin.
In addition to the search for agents with lessened toxicity, analogs which do not exhibit cross-resistivity to tumors which have become resistant to treatment with adriamycin, daunorubicin or 4-demethoxydaunorubicin continues.
The present invention provides analogs of daunorubicin and adriamycin.